Lasers are used in several practical applications including but not limited to heating, navigation, and communication. These devices employ an optically active media from which a laser beam is extracted. The beam is generated by means of a population inversion consisting of an unstable abundance of molecules having excited high energy electronic states which release photons as they decay to the equilibrium lower energy states of the optically active media.
In high energy chemical lasers, the excited electronic states are generated by a chemical reaction. For example, one such reaction involves the use of excited molecular oxygen, hereinafter referred to as singlet delta oxygen (SDO) or O2(1Δ), in combination with an optically active media or lasing substance, such as iodine or fluorine. These lasers have been found to be very useful but improved performance characteristics, especially in the area of materials supply and efficiency, is desirable. A number of problems in the generation, storage, and maintenance of the gaseous reactant materials required to produce the necessary population inversion has limited the use of these chemical lasers in military and airborne applications.
One method presently in use for generating a stream of SDO involves a chemical reaction between chlorine gas and a basic solution of hydrogen peroxide, hereinafter referred to as basic hydrogen peroxide (BHP). The excited oxygen can then be added to a suitable lasing medium and the mixture passed through an optical resonator/cavity to bring about a lasing action.
However, several problems are related to previous methods of generating SDO. Residual BHP reactant may flow into the laser nozzle and/or cavity as a contaminant, interfering with the laser gas kinetics and/or optics of the system, thereby reducing overall efficiency of laser power generation. Furthermore, large volumes of hydrogen peroxide, which is an explosive monopropellant and highly corrosive material, are required as production scale increases. Another problem is that the excited oxygen can be reduced to its unusable ground state by metal contact quenching, wall quenching, gas phase quenching, and liquid phase quenching. Therefore, to generate SDO both efficiently and in high yield, the contacting device (reactor or generator) for the gaseous and liquid reactants must provide a large interfacial area in a small volume for a short time, followed by rapid separation of the gaseous and liquid phases.
As a result, there is a need for an enhanced apparatus and method for generating SDO with greater efficiency and safety.